Expression of immediate early gene following N-methyl-N-nitrosourea-induced retinal degeneration in SD rats / 中国药理学通报

ABSTRACT

Aim To study the molecular mechanism of retinal toxicity induced by N-methyl-N-nitrosourea (MNU) in SD rats. Methods A single intraperitoneal injection of 60 mg?kg~(-1) MNU was given to 50-day-old female SD rats. After MNU treatment for different times, the rats were sacrificed and both eyes were enucleated immediately and processed for histological examination. The apoptotic index of photoreceptor cells was calculated by TUNEL labeling and the expression of c-jun and c-fos genes was detected by RT-PCR technique. Results After the application of MNU for 24 h,the disorientation of photoreceptor outer segments was seen. The outer nuclear layer and photoreceptor layer were almost completely lost at 7 d. Apoptosis had already started at 12 h post-MNU and peaked at 24 h. MNU time-dependently up-regulated the expression of c-jun and c-fos genes. Conclusion MNU has a toxic effect on retina by up-modulating expression of c-jun and c-fos genes to promote photorecptor cells apoptosis.